Diagnostic Effectiveness of whole Body Diffusion- Weighted Magnetic Resonance Imaging in Focal and Diffuse Bone Marrow Involvement in Patients with Lymphoma

Abstract

Objective:to compare diagnostic effectiveness of whole body diffusion-weighted imaging (DWI), other magnetic resonance imaging (MRI) pulse sequences and iliac wing trephine biopsy in the diagnosis of focal and diffuse bone marrow (BM) involvement in patients with lymphoma.Materials and methods.Prospective study included 130 patients with lymphoma who underwent whole-body MRI-DWI and iliac wing trephine biopsy before treatment (64 (49,2%) men, 66 (50,8%) women, middle age 43,3 ± 16,3 years, interval of 18–79 years). Hodgkin's lymphoma (HL) was at 57 (44%) patients, non-Hodgkin lymphomas (NHL) – at 73 (56%). Diagnostic effectiveness of T1- weighted images (T1-WI), STIR, DWI and FIESTA was analyzed. BM apparent diffusion coefficient (ADC) values were measured.Results.BM involvement was found in 42 patients, including 9 with HL and 33 with NHL. In HL, BM involvement was only focal. Diffuse involvement occurred more often (64%) in the NHL as compared to focal one. In focal involvement, all pulse sequences showed high diagnostic sensitivity (90–100%), BM biopsy sensitivity was 33% only. The proposed new criterion for the diagnosis of diffuse BM involvement in NHL – diffuse signal increase of the spine on DWI above renal parenchyma – has the highest sensitivity (90%) compared to T1-WI and STIR (67%) and FIESTA (71%) (p < 0.05). In NHL, the ADC value ≤0.575 • 10−3 mm2/s discrimi nates cases of diffuse involvement and absence of BM involvement with a sensitivity of 86% and a specificity of 68% (p < 0.0001). In HL, the diffuse BM signal increase on DWI is not indicative of involvement.Conclusion.All pulse sequences showed high effectiveness in the diagnosis of focal BM involvement in patients with lymphoma, iliac wing biopsy effectiveness was low. The proposed new DWI criterion for diagnosing diffuse BM involvement in NHL is the most sensitive one. A new algorithm based on whole body MRI-DWI for the diagnosis of BM involvement allows to reduce the need for BM biopsy without reducing the diagnostic effectiveness.